Get to the bottom of this mess

No one knows yet the full impact of the massive Mississippi River oil spill that has shut down a section of America's busiest waterway, disrupted water service for thousands of residents and threatened the delta's fragile ecosystem.

But it's evident that the mess demands extraordinary clean up efforts -- and a serious look at what may be done to prevent a similar disaster.

In particular, investigators need to get to the bottom of how the tug boat Mel Oliver, one of the vessels involved in the collision that caused the spill, was being operated so laxly.

Authorities said the boat's operator had only an apprentice mate's license, and no one on board was qualified to run the tugboat on the river. That's a serious violation, whether or not the Mel Oliver caused the accident, and there should be serious consequences.

But officials also should review whether the rules on who can operate boats are being diligently enforced and whether fines are serious enough to deter violators. The river is a powerful body of water, and the consequences of a mistake can be substantial -- as Wednesday's incident proved.

The collision spilled more than 400,000 gallons of industrial oil from a barge pushed by the Mel Oliver. But it could have been much worse. The other vessel involved, the double-hulled tanker Tintomara, carried 4.2 million gallons of biodiesel and about 1.3 million gallons of styrene. Fortunately, the tanker did not leak.

Still, the spill's economic disruptions are significant and growing. The Port of New Orleans alone is losing $100,000 a day. That surely pales in comparison to the combined losses of private port businesses and the owners of more than 90 vessels stranded by the river closure as of Thursday afternoon.

Restaurants and other area businesses reported losses from the drinking water disruption. And Saturday's scheduled arrival of a 2,050-passenger cruise ship also could be affected.

There are potentially long-term environmental consequences as well. Although crews are working to keep the oil out of nearby marshes, birds and other wildlife were found covered in oil. The animals affected are small in number for now, and few migratory birds use Delta National Wildlife Refuge this time of year. But refuge officials are concerned the oil could be a long-lasting contaminant of the grasses many birds eat.

It may take days to reopen the river, weeks to clean up the oily mess and months to assess the full impact. But any lessons learned to help prevent a similar disaster could last for a lifetime -- so officials should keep their eyes wide open.